Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6b76fe76de3dc24…

MALICIOUS

PDF

75.8 KB Created: 2021-10-09 01:31:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c77a30be40dfffd79c5fe55803de161d SHA-1: 0b5a2d6c178c038dde27ab930a96078af2fe63b1 SHA-256: a6b76fe76de3dc246f7b07f26314f7994be84a66af821c835d42ad5deed0a05f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is a common technique for executing malicious code. It also features a large number of external links, many pointing to compromised WordPress sites, suggesting a phishing or credential harvesting attempt. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to download further payloads or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://banktapeunadana.com/tapeunadana/bank2/admin/userfiles/file/27132519653.pdf
    • http://studioboscono.it/userfiles/files/pikanamupazodutuxo.pdf
    • https://shiprapublication.com/uniformkontakt/userfiles/image/files/zosufe.pdf
    • https://ataru.site/js/ckfinder/userfiles/files/80011186487.pdf
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/c10eaf80a1bf99fc70c061890ed591fc/17491856873.pdf
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/1613ce55970623---patav.pdf
    • http://mrcookie.tw/upload/editor/file/01052802247.pdf
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16159b7a79f8c3---kurawof.pdf
    • https://shibbirs.com/media/files/74962637802.pdf
    • http://mybyblos.com/userfiles/file/wovemifutetaxavabasab.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/16153e6f14c96d---40862221082.pdf
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613ddf4f419e1---pesuranerijanebazi.pdf
    • http://vinag7furniture.com/app/webroot/files/editor_upload/files/sipikipixuz.pdf
    • http://jnejendomsdrift.dk/userfiles/file/2489899888.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/f66f98ad42fe199ca819a822283c7732/26598082045.pdf
    • https://funbugs.ie/files/file/kajezomukojuwuxadapimatu.pdf
    • https://seedcambodia.org/htdocs/cljr/data/files/renimopusobinurovudepule.pdf
    • http://bodybybodyology.com/ckfinder/userfiles/files/52104262194.pdf
    • https://cplastik.net/data/cms/file/20853075423.pdf
    • http://www.greddy.com/admin/common/ckfinder/userfiles/File/lipuwudubaxe.pdf
    • http://cga82.com/admin/File/lokireziju.pdf
    • http://greensketch.in/userfiles/file/49033158826.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=dr+myles+munroe+books+on+relationships+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bfc7.bin
e1ab1fa1881a8a3bbdeb0c9e26fb8a1117eab072ad7f7370909ced6dcca68482
pdf-font-stream PDF embedded font (sfnt) at offset 0xBFC7 17848 bytes
font_01_sfnt_off0000edd3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD3 16792 bytes
font_02_sfnt_off000105ea.bin
4cf440995576db3e80a01a968f9fb52b132d13ab7f8d6b78b867b45f5ccda07e
pdf-font-stream PDF embedded font (sfnt) at offset 0x105EA 11208 bytes